[Tutor] Getting name of Widget for event.widget?

[Peter Otten]

Leam Hall wrote:

> Note that this is for an on-line class so I'd appreciate pointers to
> what I need to read or think about more than the answer out right.
> 
> Using Python 3 on Linux, is there a way to get the name of a widget
> instead of numeric representations in event.widget?
> 
> What I tried were a few variations of:
> 
>      def small_frame_handler1(self, event):
>          print(event.widget, " clicked at ", event.x, event.y)
> 
> and got:
> 
>      .140937484.144713004  clicked at  350 39

The above is actually a name in Tcl, automatically generated by tkinter.
 
> Called by:
> 
>         frame1 = Frame(self, bg="blue")
>         frame1.grid(row=0, column=0, rowspan=1, columnspan=2, sticky=ALL)
>         frame1.bind("<Button-1>", self.small_frame_handler1)
> 
> I tried to send parameters in the "bind" but kept getting argument
> mis-matches. There are two frames and I'd like to be able to put the
> name of the frame in the print without having to have a separate method
> for each one. This is inside a class, if that makes a difference.

You can either provide a custom name (tkinter will still add a leading dot)

import tkinter as tk

root = tk.Tk()

def frame_handler(event):
    print(event.widget)

for row, color in enumerate(["red", "blue"]):
    frame = tk.Frame(root, bg=color, name=color + "_frame")
    frame.grid(row=row, column=0, sticky="nsew")
    frame.bind("<Button-1>", frame_handler)
    root.rowconfigure(row, weight=1)
root.columnconfigure(0, weight=1)
root.geometry("200x200+100+200")
root.mainloop()

set a custom attribute

...
def frame_handler(event):
    print(event.widget.my_name)

for row, color in enumerate(["red", "blue"]):
    frame = tk.Frame(root, bg=color)
    frame.my_name = color + "_frame"
    frame.grid(row=row, column=0, sticky="nsew")
    frame.bind("<Button-1>", frame_handler)
    root.rowconfigure(row, weight=1)
...

or use a more general mechanism with functools.partial:

import tkinter as tk
from functools import partial

root = tk.Tk()

def frame_handler(event, widget_name):
    print(widget_name)

for row, color in enumerate(["red", "blue"]):
    frame = tk.Frame(root, bg=color)
    frame.grid(row=row, column=0, sticky="nsew")
    frame.bind("<Button-1>", partial(frame_handler, widget_name=color + 
"_frame"))
...